Their swords are rust,their bones are dust,Their souls are with the saints,we trust.- Samuel Taylor Coleridge.

Until the last few decades, the Crusaders were regarded as romantic figures. Walter Scott included a number of them in his novels, and quotes the lines above from Coleridge in Ivanhoe.

In the Robin Hood legends, King Richard's heroics in the Holy Land masked the Lionheart's actual role as a French-speaking monarch who treated England as a milch-cow to finance his territorial ambitions across the Channel.

The word Crusader was incorporated into the names of sports teams and Christian organisations, and was even used as a trademark for various products (Australians over a certain age will remember the Crusader brand of men's suiting).

The Crusades were attempts by the Roman Catholic countries of Europe, led by the Pope, and helped intermittently by the Erastian combination of Eastern empire and Greek Orthodox Church based at Constantinople, to win control of Palestine, particularly Jerusalem, from the Muslims.

There were eight Crusades during the period 1095-1291, and they were ultimately unsuccessful.

Jerusalem was taken in 1099, but its reoccupation by the Muslims in 1187 was followed by the gradual loss of all other Crusader possessions.

The following summary of the overwhelmingly fashionable current view of the Crusades might sound like caricature or travesty, but is not.

Here goes: The barbaric and bloodthirsty Christian West launched a brutal, unprovoked attack on the cultured, peaceful and tolerant Islamic civilisation in an imperialist attempt to win territory and trade, subjugate foreign peoples and force conversions.

Variations on this theme can be found in both lowbrow and highbrow culture.

The 2005 film about the Crusades, Kingdom of Heaven, presented what the mediaevalist Jonathan Riley-Smith described as "Osama bin Laden's version of history".

Academic discourse uses Edward Said's allegations in his Orientalism of the Western manufacture of "the Other" to elaborate its conspiracy theory about Western "Islamophobia".

For the 900th anniversary of the capture of Jerusalem, a group of Christians retraced the route of the First Crusade during 1999, apologising to Muslims along the way.

Certainly, some have argued that the New Testament envisages neither the union of church and state controlling armed force which emerged after 312 under the Roman Emperor Constantine, nor the cult of relics, holy sites and pilgrimages which made Palestine such a revered destination for Europeans.

However, given that these two phenomena had come into existence by the 11th century, how should we assess the Crusades?

It might be useful to list each of the myths associated with the subject, followed by Rodney Stark's exposure of it.

Myth Number One: Muslims have never forgotten nor forgiven the Crusades, and have nursed a bitter resentment of them for a millennium.

Reality: Muslim rancour about the Crusades did not emerge until the early 20th century, and did not become extreme until after the founding of the state of Israel.

Myth Number Two: The Crusades were unprovoked.

Reality: The Crusades were precipitated in the long-term by four and a half centuries of militant Muslim colonisation of the Middle East, North Africa, the Mediterranean and Spain, with the accompanying subjugation of the church in those places, and by recent bloody attacks on pilgrims and the Holy Land.

Myth Number Three: The Crusaders were motivated primarily by a desire for wealth and forced conversions.

Reality: Those who "took the cross" were financially impoverished by the expense of crusading; the Crusader kingdoms, far from existing on the exploitation of the population, had to be supported with subsidies from Europe; and there was no program of forced conversions.

Myth Number Four: The world of Islam was cultured, peaceful and tolerant.

Reality: Science and learning within Islam were largely derivative and inferior to the West's; Muslims perpetrated atrocities against Christian pilgrims; Muslim countries forced their resident populations of Christians to live in a servile state of dhimmitude.

Stark is not, and does not claim to be, an historian of the Crusades (he drops at least one clanger by having friars preaching Urban II's First Crusade in the late 11th century, despite the fact that friars did not come into existence until the early 13th century).

He does an admirable job, however, of providing a concise introduction to them, and of alerting readers to the ways in which they are being polemically distorted and exploited.